Pell says he's innocent of abuse claims

Cardinal George Pell maintains he is innocent of historical child sexual assault allegations as police decide whether to charge Australia's most senior Catholic.

Victoria Police say they will take time to consider whether charges are laid after receiving final advice from the state's Director of Public Prosecutions about the allegations, which Cardinal Pell has repeatedly denied.

"I'd just like to restate my innocence," Cardinal Pell told reporters in Rome on Wednesday.

"I stand by everything I've said at the royal commission and in other places.

"We have to respect due process, wait until it's concluded and obviously I'll continue to co-operate fully."

When asked if he would be prepared to go to Australia, he answered: "I will continue to cooperate fully."

Australia does not have an extradition treaty with the Vatican, which could potentially complicate matters if Cardinal Pell is charged unless he voluntarily returns to Australia.

However, Australian National University professor of international law Donald Rothwell believes Cardinal Pell would want to return to Australia to mount a vigorous defence if charged.

Cardinal Pell, who, as the Vatican's finance chief is considered the third most powerful person in the Catholic Church, has said each and every allegation of abuse and cover-up against him is false.

The allegations against the former Ballarat priest and Melbourne and Sydney archbishop were repeated in a book published this week, which Cardinal Pell's office in Rome labelled "an exercise in character assassination".

Sydney Archbishop Anthony Fisher said Cardinal Pell is the victim of relentless character attacks and justice must be left to run its course.

"What is clear, however, is that Cardinal Pell has co-operated in every way with multiple police, parliamentary and royal commission investigations."